Shortly after midnight Wednesday, the last Golden Gate Bridge toll collector left her booth for the final time, signaling the end of an era.

Drivers crossing the historic bridge are no longer able to pay their tolls with cash or be greeted by a human being. With the flip of a switch, the Golden Gate Bridge, Highway and Transportation District implemented a $3.2 million all-electronic collection system.

Marilyn Alvarado was the last toll collector on the bridge early Wednesday morning. After more than 29 years of service, she plans to retire. She said her last day of work was an amazing one filled with mixed feelings of sadness and happiness.

"I want to thank the public for all their kind words and generosity," Alvarado said. "We've had so much generous support."

Alvarado took her last toll from Jim Eddie, bridge district president from Mendocino County, and his passenger Brian Sobel, district board member from Sonoma County. Eddie drove a maroon 1937 Packard through Alvarado's lane, an act he said is historically significant.

"It actually was the first car to cross the bridge when they opened it in 1937," Eddie said.

The second-to-last last car through the toll booth was driven by San Francisco resident Peter Lavezzoli, who said he loves the toll-takers and will miss interacting with them.

"I think it means that we're more interested in conveniences as opposed to human interaction," Lavezzoli said. "It's another step toward the de-humanization of our society."

Before Alvarado left her lane No. 1 booth, workers were busy unveiling new signs that said "Do Not Stop" and painting the toll booth windows in the international orange used to paint the bridge. Signs raising the speed limit from 5 mph to 25 mph were also unveiled, along with signs making lane No. 2 at the Toll Plaza as a $3 toll carpool lane. Three people in a vehicle qualify as a carpool.

Toll collector Dawnette Reed waited near the Toll Plaza late Tuesday night with flowers for her sister Tracy Sorrell, who was the second-to-last toll-taker on the bridge. Reed, who had worked earlier in the day, said it was a difficult day filled with tears. She said her faithful customers showed an outpouring of support.

"I had a lot of customers who wanted to hug me. I got four bouquets of flowers, coffee, multiple cards, gift cards and baked goods," Reed said.

She said it's difficult to leave a job she's grown up with. She's worked as a toll-taker for 18 years after starting her work with the district as a gift shop employee at the age of 16. In all her time on the bridge, she said she's seen everything from people walking away from their cars to driving through the toll booths naked.

"I really loved my job," Reed said, adding that she's now seeking work with the Bay Area Rapid Transit District.

Reed was one of the full-time toll-takers and 29 temporary, part-time hires affected by the switch. Toll takers like were eliminated in an attempt to save the bridge district money, as it's facing a $66 million budget shortfall over the next five years. Bridge district managers anticipate saving about $16 million over eight years in salaries and benefits. The base annual salary for a toll-taker ranged from $48,672 to $54,080.

Eddie said the change is difficult as most bridge employees have great longevity with the district, typically retiring from their jobs instead of being forced out.

"It's a real change, but technology has got its place and it's here to stay," Eddie said.

Under the new system, drivers will pay their tolls using digital transponders that deduct money from a prepaid account or credit card, or through license plate scans that automatically send bills to drivers. Those who want to pre-pay a toll with cash can pay at "Touch-N-Buy" kiosks around Marin, often found in convenience stores. Cash will no longer be accepted at the Toll Plaza.

The district has established a website -- www.goldengate.org/tolls -- to provide information to drivers about their payment choices.

Drivers who fail to pay the toll via one of the electronic options will receive warning letters and could eventually have a hold placed on their vehicle registration at the California Department of Motor Vehicles.

As a man's voice shouted over a loudspeaker early Wednesday at confused drivers, telling them not to stop at the unmanned booths, toll-worker Cheryl Butler-Adams reflected on her short five months working at the bridge.

"It was a job, but it was enjoyable. You weren't just taking cash, you were always assisting people," Butler-Adams said.